Correctly manage icon state when visibility is lost.

src/sound/icon.rs

@@ -194,9 +194,10 @@ fn update<S>(
                             entity.remove::<Rolloff>();
                         });
                     }
+                } else if !sound.paused {
+                    sound.paused = true;
+                    sound.restart = true;
                 }
-            } else {
-                sound.paused = true;
             }
         }
     }